ABO Antigen Expression in Graft Tissue: Is Titration Against Donor Erythrocytes Relevant?

Abstract

ABO-incompatible living donor renal transplantation has become an accepted treatment for end-stage renal disease. Two main factors appear to be important when crossing the ABO barrier, the donor organ A/B antigen expression and the amount of recipient anti-A/B antibody. Antigen expression depends on the ABO blood group and subgroup and may vary in different tissues and cells. The amount of recipient anti-A/B antibody, determined by titration, is very variable. One major drawback with titration is the lack of conformity between different laboratories, making comparisons difficult. For clinical use, the anti-A/B antibody titration technique has to be simple, rapid, and cheap, in addition to being accurate. Although there is a need for more standardized procedures for determination of ABO antibodies, existing techniques are sufficient in the clinical care of patients. To illustrate the variation in susceptibility of different graft tissues to ABO antibodies, in this paper we describe a case of an ABO-incompatible combined liver and kidney transplantation.

Immunogenicity and Allogenicity: A Challenge of Stem Cell Therapy

“…However, there is variation in the level of expression of the ABO antigens as well as in the location where the antigens are expressed. In cardiac tissue, ABO antigens are found on the endothelium, the epicardium, and the endocardium [11]; in kidney they are found on peritubular vessels, distal tubuli, and faintly on glomerulus [12]; while in liver, bile ducts and venules express ABO but not hepatocytes [13]. Preformed natural antibodies to ABO antigens that can be produced by 0.25% [14] have long been appreciated to constitute a profound barrier to transplantation.…”

ABO-incompatible kidney transplantation

“…However, there seem to be many detailed technical differences and large interinstitutional variations in the titration of anti-ABO antibodies. When four different techniques were compared, the Tube Technique, BioVue Column Agglutination Technology, DiaMed-ID Micro Typing System, and flow cytometry (FCM), only the FCM technique yielded a very consistent outcome in repeated measurements [9,10]. The titer level at which a renal transplantation can safely be performed has not unequivocally been established not at least due to methodical problems as mentioned above.…”

Characteristics, Detection, and Clinical Relevance of Alloantibodies in Kidney Transplantation

“…The ABO system also plays an important role in kidney allocation; donors and recipients must be either ABO identical or compatible (Futagawa & Terasaki, 2006). A/B antigens are known to be passively absorbed by different tissues of the kidney, including the glomerular endothelium and the tubular epithelium (Rivera & Scornik, 1986, Aikawa et al, 2003Fidler et al, 2004;Rydberg et al, 2007). Endothelial and epithelial cell surface densities of A/B antigens are also different.…”

“…In addition, Alkhunaizi reports that up to 8% of A2 individuals have anti-A1 IgG antibodies in their sera (Alkhunaizi, 2006). Anti-A1 IgG antibody titers of less than or equal to 1:8 have been considered to be a cut-off for assuming a low risk of AMR (Gloor & Stegall, 2007;Jordan et al, 2009;Rydberg et al, 2007;Warren et al, 2004). Additional therapeutic measures are required when titers of anti-A1 IgG antibodies are high, such as plasma exchange that is accompanied by a bimonthly monitoring of anti-A1 titers (Montgomery & Locke, 2007;Tobian et al, 2009;Tyden et al, 2010;Winters et al, 2004).…”

“…A rebound effect was observed in only one of eleven recipients after 36 months post-transplantation. Notably, no differences in graft survival time between ABOi and ABO-compatible transplantations were observed (Rydberg et al, 2007;Tyden et al, 2005). Five years ago, the John Hopkins Transplant Center established a DS protocol for ABOi transplantation, which consisted of PP, IVIG and Rituxan administration Tobian et al, 2009).…”